## Comment Re: Looking more and more likely all the time... (Score 1) 501 501

Sorry ,that is rubbish. The cars don't move anymore due to friction, they would still move if it was the collision of spaceships for example. And impulse is not just a mathematical construct, it is an important quantity in physics. The conservation of impulse is used to make mechanical calculations. It gives additional constraints to the conservation of energy, and there is no other conserved entity that gives these contraints.